// -*- C++ -*-
/*
 *
 * Template Numerical Toolkit (TNT)
 *
 * Mathematical and Computational Sciences Division
 * National Institute of Technology,
 * Gaithersburg, MD USA
 *
 *
 * This software was developed at the National Institute of Standards and
 * Technology (NIST) by employees of the Federal Government in the course
 * of their official duties. Pursuant to title 17 Section 105 of the
 * United States Code, this software is not subject to copyright protection
 * and is in the public domain. NIST assumes no responsibility whatsoever for
 * its use by other parties, and makes no guarantees, expressed or implied,
 * about its quality, reliability, or any other characteristic.
 *
 */

#ifndef TNT_FORTRAN_ARRAY1D_H
#define TNT_FORTRAN_ARRAY1D_H

#include <cstdlib>
#include <iostream>

#ifdef TNT_BOUNDS_CHECK
#include <cassert>
#endif

#include "tnt/i_refvec.h"

namespace TNT {

template <class T> class Fortran_Array1D {

private:
  i_refvec<T> v_;
  int n_;
  T *data_; /* this normally points to v_.begin(), but
* could also point to a portion (subvector)
* of v_.
*/

  void initialize_(int n);
  void copy_(T *p, const T *q, int len) const;
  void set_(T *begin, T *end, const T &val);

public:
  typedef T value_type;

  Fortran_Array1D();
  explicit Fortran_Array1D(int n);
  Fortran_Array1D(int n, const T &a);
  Fortran_Array1D(int n, const T *a);
  inline Fortran_Array1D(const Fortran_Array1D &A);
  inline Fortran_Array1D &operator=(const T &a);
  inline Fortran_Array1D &operator=(const Fortran_Array1D &A);
  inline Fortran_Array1D &ref(const Fortran_Array1D &A);
  Fortran_Array1D copy() const;
  Fortran_Array1D &inject(const Fortran_Array1D &A);
  inline T &operator()(int i);
  inline const T &operator()(int i) const;
  inline int dim1() const;
  inline int dim() const;
  ~Fortran_Array1D();

  /* ... extended interface ... */

  inline int ref_count() const;
  inline Fortran_Array1D<T> subarray(int i0, int i1);
};

template <class T>
Fortran_Array1D<T>::Fortran_Array1D()
    : v_(), n_(0), data_(0) {}

template <class T>
Fortran_Array1D<T>::Fortran_Array1D(const Fortran_Array1D<T> &A)
    : v_(A.v_), n_(A.n_), data_(A.data_) {
#ifdef TNT_DEBUG
  std::cout << "Created Fortran_Array1D(const Fortran_Array1D<T> &A) \n";
#endif
}

template <class T>
Fortran_Array1D<T>::Fortran_Array1D(int n)
    : v_(n), n_(n), data_(v_.begin()) {
#ifdef TNT_DEBUG
  std::cout << "Created Fortran_Array1D(int n) \n";
#endif
}

template <class T>
Fortran_Array1D<T>::Fortran_Array1D(int n, const T &val)
    : v_(n), n_(n), data_(v_.begin()) {
#ifdef TNT_DEBUG
  std::cout << "Created Fortran_Array1D(int n, const T& val) \n";
#endif
  set_(data_, data_ + n, val);
}

template <class T>
Fortran_Array1D<T>::Fortran_Array1D(int n, const T *a)
    : v_(a), n_(n), data_(v_.begin()) {
#ifdef TNT_DEBUG
  std::cout << "Created Fortran_Array1D(int n, T* a) \n";
#endif
}

template <class T> inline T &Fortran_Array1D<T>::operator()(int i) {
#ifdef TNT_BOUNDS_CHECK
  assert(i >= 1);
  assert(i <= n_);
#endif
  return data_[i - 1];
}

template <class T> inline const T &Fortran_Array1D<T>::operator()(int i) const {
#ifdef TNT_BOUNDS_CHECK
  assert(i >= 1);
  assert(i <= n_);
#endif
  return data_[i - 1];
}

template <class T>
Fortran_Array1D<T> &Fortran_Array1D<T>::operator=(const T &a) {
  set_(data_, data_ + n_, a);
  return *this;
}

template <class T> Fortran_Array1D<T> Fortran_Array1D<T>::copy() const {
  Fortran_Array1D A(n_);
  copy_(A.data_, data_, n_);

  return A;
}

template <class T>
Fortran_Array1D<T> &Fortran_Array1D<T>::inject(const Fortran_Array1D &A) {
  if (A.n_ == n_)
    copy_(data_, A.data_, n_);

  return *this;
}

template <class T>
Fortran_Array1D<T> &Fortran_Array1D<T>::ref(const Fortran_Array1D<T> &A) {
  if (this != &A) {
    v_ = A.v_; /* operator= handles the reference counting. */
    n_ = A.n_;
    data_ = A.data_;
  }
  return *this;
}

template <class T>
Fortran_Array1D<T> &Fortran_Array1D<T>::operator=(const Fortran_Array1D<T> &A) {
  return ref(A);
}

template <class T> inline int Fortran_Array1D<T>::dim1() const { return n_; }

template <class T> inline int Fortran_Array1D<T>::dim() const { return n_; }

template <class T> Fortran_Array1D<T>::~Fortran_Array1D() {}

/* ............................ exented interface ......................*/

template <class T> inline int Fortran_Array1D<T>::ref_count() const {
  return v_.ref_count();
}

template <class T>
inline Fortran_Array1D<T> Fortran_Array1D<T>::subarray(int i0, int i1) {
#ifdef TNT_DEBUG
  std::cout << "entered subarray. \n";
#endif
  if (i0 > 0 && i1 < n_ && i0 <= i1) {
    Fortran_Array1D<T> X(*this); /* create a new instance of this array. */
    X.n_ = i1 - i0 + 1;
    X.data_ += i0;

    return X;
  } else {
#ifdef TNT_DEBUG
    std::cout << "subarray:  null return.\n";
#endif
    return Fortran_Array1D<T>();
  }
}

/* private internal functions */

template <class T> void Fortran_Array1D<T>::set_(T *begin, T *end, const T &a) {
  for (T *p = begin; p < end; p++)
    *p = a;
}

template <class T>
void Fortran_Array1D<T>::copy_(T *p, const T *q, int len) const {
  T *end = p + len;
  while (p < end)
    *p++ = *q++;
}

} /* namespace TNT */

#endif
/* TNT_FORTRAN_ARRAY1D_H */
